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1.
Early childhood is a sensitive period for learning and social skill development. The maturation of cerebral regions underlying social processing lays the foundation for later social-emotional competence. This study explored myelin changes in social brain regions and their association with changes in parent-rated social-emotional development in a cohort of 129 children (64 females, 0–36 months, 77 White). Results reveal a steep increase in myelination throughout the social brain in the first 3 years of life that is significantly associated with social-emotional development scores. These findings add knowledge to the emerging picture of social brain development by describing neural underpinnings of human social behavior. They can contribute to identifying age-/stage-appropriate early life factors in this developmental domain.  相似文献   
2.
Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later.  相似文献   
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ABSTRACT

The aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time.  相似文献   
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5.
In this digital ITEMS module, Dr. Jeffrey Harring and Ms. Tessa Johnson introduce the linear mixed effects (LME) model as a flexible general framework for simultaneously modeling continuous repeated measures data with a scientifically defensible function that adequately summarizes both individual change as well as the average response. The module begins with a nontechnical overview of longitudinal data analyses drawing distinctions with cross-sectional analyses in terms of research questions to be addressed. Nuances of longitudinal designs, timing of measurements, and the real possibility of missing data are then discussed. The three interconnected components of the LME model—(1) a model for individual and mean response profiles, (2) a model to characterize the covariation among the time-specific residuals, and (3) a set of models that summarize the extent that individual coefficients vary—are discussed in the context of the set of activities comprising an analysis. Finally, they demonstrate how to estimate the linear mixed effects model within an open-source environment (R). The digital module contains sample R code, diagnostic quiz questions, hands-on activities in R, curated resources, and a glossary.  相似文献   
6.
现代设备复杂系数的不断提高,导致对设备维修技术专家的需求日益增大。基于网络视频的设备远程维修系统的出现,为缓解设备维修技术力量短缺的矛盾提供了新的解决方式。  相似文献   
7.
对体育教学与运动训练异同的研究   总被引:4,自引:0,他引:4  
黄秋玲 《体育科技》2003,24(2):88-90
对体育教学和运动训练的概念、目的、手段、方法、内容、本质和运动负荷等进行比较分析 ,旨在使体育工作者能更好地区别两者的异同点 ,为体育教学和运动训练的改革提供参考依据。  相似文献   
8.
AMP激活的蛋白激酶(AMPK)不仅可以作为细胞水平的能量感受器,还可以通过细胞因子参与调节机体整体的能量消耗和能量摄人。运动等应激可以激活AMPK。参与调节骨骼肌葡萄糖代谢和脂肪酸氧化等能量代谢过程。运动训练可影响骨骼肌AMPK基因表达,进而参与到运动训练的机体适应机制。  相似文献   
9.
黄河 《体育科技》2005,26(4):7-10
广西大开发中体育产业化发展的关键是要解决体育资源的优化配置,实现体育要素的竞争,充分体现体育市场机制的运行,实行体育市场化的管理,与此同时要处理好市场经济条件下发展体育市场化的几个矛盾,包括体育内部的矛盾,新旧体制的矛盾,经济方式和利益分配方式的变革等矛盾;广西大开发中体育市场化发展首要的是政治和经济条件,其基本措施是要明确体育市场化的基本途径,要明确体育市场化发展的原则及其具有的巨大作用;要明确推进体育市场化的有效措施,从广西地区的实际出发,立足体育资源优势。  相似文献   
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